Hardware required: PC, running Windows 3.1or 95 with CD-ROM

Software requirements: Mac System 7.1 , PC. Windows 3.1/ 95

Pre-requisite for study of the program: GCSE chemistry or equivalent

Documentation: The only information supplied with the CD ROM was the installation instructions.
These were straightforward and the set-up instructions guided you easily through all the necessary steps, including the set-up for Quicktime, requires for the running of the program.

The Program: On accessing the program you are automatically taken through a number of pages with details of the PCCAL consortium until you reach the index where topics for the study are listed:
Bonding.
Isomerism
Nucleic Acids
Proteins
Carbohydrates
Lipids
Each topic is accessed by selecting the appropriate button on the index page or from the Map. Each section can be studied as a stand-alone package and provides a good introduction to the particular subject area.
The program assumes a background of GCSE chemistry or its equivalent.
Having selected a topic to study the aims are clearly stated.
As you move into the topic you are presented by a series of pages that ere navigated using the buttons on the navigation bar and on-screen hotwords and additional buttons.
Self assessment questions are interspersed at frequent intervals with the instructional material.
Feedback is given in the form of a simple correct/incorrect response and if incorrect the user is prompted to make additional attempts. It is a pity that a more comprehensive feedback, perhaps tailored to the user’s specific response, is not provided since this would greatly reinforce the teaching material
Overall the program is extremely well designed with the hotwords allowing more in-depth study of a particular topic.
The page layout is very clear, with large type providing screens that are easy to read ( at no time are we presented with crowded screens).
The diagrams are clear with a good use of colour. Animations are well used to provide additional clarification where necessary and are very clear and informative.
The six topic areas are not all covered to the same depth. The treatment of nucleic acids in particular
is far more rigorous. An equal weighting of topics might have been more appropriate.

1 Bonding: This topic provides a full introduction to the bonding in organic/biological molecules although there is some over-simplification at times. The strength of an ionic bond is portrayed as being stronger than a covalent bond: since we are mostly concerned with molecules in an aqueous environment this could be confusing .

2. Isomerism: here is a very clear and well presented discussion of the topic with a number of very useful animations.
The subject of optical isomerism is particularly well discussed with the diagrams and animations bringing clarity to an area which is often difficult for a student to visualise. The rules for assigning the Absolute Configuration (R and S nomenclature) to structures are fully considered but Relative Configuration and Fischer projections, which are widely used in the consideration of biological molecules, are not even mentioned.
The use of self assessment in programs of this type is essential but there are occasions when they do not add anything to the learning process. We are presented by one in this section where the student is asked to select a precise wavelength of the D line of sodium.

3 Nucleic Acids: This topic is very extensively covered. The structure and function of nucleic acids is introduced in such a way that it leads into a consideration of the replication of DNA, RNA synthesis, translation and transcription.
Unfortunately the role of ribosome in protein synthesis is not made clear (at least at the beginning of the topic) and one might in fact gain the impression that the mitochondrion is the main site of protein synthesis.
This topic makes extensive and excellent use of diagrams and animations to give a very clear exposition of the topic, unfortunately the diagram which is meant to show bonding to the 1’ carbon of the sugar molecule actually shows bonding to the 5’ carbon It would be well worth ensuring the correction is made

4. Proteins: This topic is not treated as extensively as nucleic acids but it is a good introductory account with good use of diagrams and animation
The only programming problem is in the self assessment on page16 of the topic when the user is presented with options which show possible reaction sequences for the formation of a peptide linkage. By selecting the correct answer the response "well done " is given, but a box appears around an incorrect answer.

5. Carbohydrates: Arguably this class of biomolecules provides most difficulty for students and is the most difficult to teach.
We feel that students will find this section very useful since it emphasises the main points about structure and function without becoming too complex. The presentation of the various ways in which sugar molecules can link together was particularly clear.
However we are surprised to find no reference to "anomers" of sugars and he configuration of the anomeric _OH. In the section on monosaccharides perhaps the formula for fructose should have been presented in the furanose form (rather than the pyranose), since it is this form that occurs in sucrose (shown later in this topic).
We were also slightly bemused that one of the self assessment questions expected the user to know the "correct " name for sucrose was saccharobiose – a name we were unable to find in a range of modern biochemistry texts!

6. Lipids: Again, this topic related chemical structure to function without becoming too involved in the complexity of structure in lipids.
We particularly liked the animation which showed how cholesterol is incorporated into the lipid bilayer.

Conclusion:
We feel that this program would be a very useful resource for anyone involved with teaching introductory biochemistry.
It covers the main aspects of biomolecules from both a biological and chemical point of view.
The program uses hotwords, diagrams and animations very effectively, thereby achieving a level of clarification and explanation that is not possible with a textbook. The layout of the pages is user friendly and will not intimidate the students.
The integration of self assessment questions serves to engage the user more fully with the material.
This is version 2 of the program which undoubtedly will prove very useful to many studying introductory biochemistry. We look forward to version 3 which will remove the few problems that still exist.